Canopies are created before the vines are planted

Transcription

Canopies are created before the vines are planted
Canopy Management for Disease Control in Wine Grapes
Grape IPM Workshop
March, 2011
Mark L. Chien
State-wide Viticulture Educator
Penn State Cooperative Extension
mlc12@psu.edu
Environmental and viticultural inputs that impact on grape quality and composition
Strive for balance, harmony and equilibrium in the vine and ecosystem
Why are canopy and fruit zone management
strategies important?
• Great wine demands ripe and clean fruit
• In any given year, no viticultural practices can impact the final outcome of
fruit quality more: you can do it!
• It works for all species, varieties, clones of grape vines intended to make
good wine!
Merlot on VSP at
Waltz Vineyard in
Manheim
Benefits of a Good Canopy Microclimate
• Enhancing the microclimate of the vine: entry of light and air into the canopy
environment offers…
– Lower incidence of almost all diseases by reducing humidity levels and
allowing sunlight and wind to dry out leaves and fruit
– Improve spray penetration to interior of the canopy
– Allows sunlight to penetrate into the canopy interior for more efficient
photosynthesis
– Affects fruit zone temperature range allowing more efficient biosynthesis
of essential compounds
– Helps to reduce levels of methoxypyrazines (green, herbal flavors in red
wines) in berries
– Looks better, makes the grapes appear/are better quality and thus wine.
Wine makes like tidy canopies for their wines
Canopies are created before the vines are planted:
modesty is the best policy!
• Start with knowing wine type, style and price point
• Find the correct site to grow this wine
• Site evaluation: determining potential vine size and balance
– Soil fertility and plant available water
– Climate: amount of sun and rainfall (annual and growing season)
• Macro effects: rain shadows, hurricanes, low winter temperature, frost
• Microeffects: canopy size and shape
• Local environmental factors
– Seek convex surfaces
– Trees are bad
– Avoid low areas that are more damp in soil and air
Unbalanced big vine in Napa Valley
12x8 spacing, 1 wire vertical
California sprawl system
Balanced small vine at Chateau
Petrus, 1.2m x 1m VSP
•
Vineyard Design will Affect Canopy Size
and Shape
Plant materials
–
–
–
–
–
Varieties: natives and hybrids are naturally more disease resistant
Vine morphology: small leaves, loose clusters, longer internodes
Natural vine vigor: e.g. Cabernet Sauvignon is a BIG vine
Rootstock effects on vine size and vigor
Plant healthy, certified vines and then take care of them!
• Trellis and training systems
–
–
–
–
–
Single or divided canopies
Head/cane vs. cordon/spur pruning and training
Low or high fruit position
Fruit wire height: effects on microclimate
Getting spray materials where they are needed, low or high
• Row direction: with the wind or the sun?
Vine Density: fitting the vine into the right space
•
•
•
•
Harmony, equilibrium and balance in the canopy
What is the correct vine size?
How to achieve a balance vine
Effects of size and balance on wine quality
Juan in 1m x 1m at Mondavi
Lyre system on 12x6 in Napa
Influence of vine spacing on canopy architecture
Too Narrow
Optimum
Keep it open, but not too open
Too Wide
From: Intrieri and Filipetti American Journal of Enology and
Viticulture, 50th Anniversary
Canopy Architecture
• Regulating vine vigor: 1 to 1.5 leaf layers helps all problems
with disease!
– Dappled light.
– The t-shirt effect.
– Check the shadow in mid morning and afternoon
• Evenly spaced, vertical shoots (up or down)
Canopy Management Practices
•
•
•
•
•
•
•
•
Dormant pruning: balance begins in the winter
Manage the head and ends of the vine carefully
Manage low and high suckers, shoot thinning
If you have more than one cane or cordon or any combination per side of
vine
Correct timing of positioning is oh, OH so critical to success! June is
crunch month: grand period of growth.
Shoot position like you mean it. Make them stand straight and steady.
Fasten wires or shoots to maintain position
Exposure and aeration comes from leaf and lateral removal, shoot and
cluster positioning. Timing and severity are important.
Hedge as much as you need to, no more or less
Find and Emulate Good Canopies
Vertical shoot positioned Pinot Noir at Chaddsford
Marquette on high wire cane pruned at Lincoln Peak Vineyard in Vermont
Veraison and Harvest: crunch time for canopies
• Stop those shoot tips from growing!
• Late whites and reds still need good canopies for 4-6 weeks
– Disease control, especially PM, DM and late harvest rots
– The danger of broccoli tops
– Complications of netting
• Getting the fruit fully mature. Fruit zone architecture
• Building up carbohydrate (flesh and fuel) for overwintering
and spring growth
Fruit Zone Management for Disease Control
•
•
•
•
Keep clusters well spaced and separated (i.e. shoots positioned)
Fruit zone open to allow spray penetration
Effectiveness of late season sprays
Critical temperature needs related to fruit ripening processes
– Photosynthesis
– Flavors, color, tannin, methoxypyrazines
Waiting for Pinot Noir to ripen in Ontario
When to Divide (or undivide)
• Greater (or less) than 0.4 lb of pruning weight per foot of trellis
• Vertical vs. horizontal systems
– Scott Henry, Smart-Dyson
– Lyre (Carbonneau), Geneva Double Curtain
• Developing the divided trellis and training system
Scott Henry training at
Paradocx Vineyard in
Chester County
Perfectly trained Norton on Geneva Double Curtain
at Chrysalis Vineyard in Virginia
Canopy Management = People
• Skilled labor and supervision
– Have the people ready when you need them
– Be out there working with the crew
– Have the money available to pay the crew
• Timing is absolutely critical to successful canopy management
–
–
–
–
Early tasks
Watch the weather
Grand period of growth
Late season
• Labor costs are typically 50-60 percent of vineyard operating
expenses. Be prepared!
Canopy management is not enough
• Equipment
– High quality, properly sized and designed spray system for the vineyard
– Correct tractor HP and PTO power
– Positive pressure spray cab for operator
• Calibration: correct rate, speed, nozzle selection
• Materials
– Chemicals
– Water
– surfactant
• Timing
– time of day and conditions
– Time of season and plant stage
• Operator: a skilled tractor driver and sprayer operator
Reference resources:
2011 NY-PA: http://ipmguidelines.org/grapes/
Sunlight into Wine